FlexLexer.h

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// -*-C++-*-
// FlexLexer.h -- define interfaces for lexical analyzer classes generated
// by flex

// Copyright (c) 1993 The Regents of the University of California.
// All rights reserved.
//
// This code is derived from software contributed to Berkeley by
// Kent Williams and Tom Epperly.
//
//  Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions
//  are met:

//  1. Redistributions of source code must retain the above copyright
//  notice, this list of conditions and the following disclaimer.
//  2. Redistributions in binary form must reproduce the above copyright
//  notice, this list of conditions and the following disclaimer in the
//  documentation and/or other materials provided with the distribution.

//  Neither the name of the University nor the names of its contributors
//  may be used to endorse or promote products derived from this software
//  without specific prior written permission.

//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
//  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
//  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
//  PURPOSE.

// This file defines FlexLexer, an abstract class which specifies the
// external interface provided to flex C++ lexer objects, and yyFlexLexer,
// which defines a particular lexer class.
//
// If you want to create multiple lexer classes, you use the -P flag
// to rename each yyFlexLexer to some other xxFlexLexer.  You then
// include <FlexLexer.h> in your other sources once per lexer class:
//
// #undef yyFlexLexer
// #define yyFlexLexer xxFlexLexer
// #include <FlexLexer.h>
//
// #undef yyFlexLexer
// #define yyFlexLexer zzFlexLexer
// #include <FlexLexer.h>
// ...

#ifndef __FLEX_LEXER_H
// Never included before - need to define base class.
#define __FLEX_LEXER_H

#include "aprepro_parser.h"

extern "C++" {

struct yy_buffer_state;
typedef int yy_state_type;

class FlexLexer
{
public:
  FlexLexer() : yytext(nullptr), yyleng(0), yylineno(0), yy_flex_debug(0) {}
  virtual ~FlexLexer() {}

  const char *YYText() const { return yytext; }
  int         YYLeng() const { return yyleng; }

  virtual void                    yy_switch_to_buffer(struct yy_buffer_state *new_buffer) = 0;
  virtual struct yy_buffer_state *yy_create_buffer(std::istream *s, int size)             = 0;
  virtual void                    yy_delete_buffer(struct yy_buffer_state *b)             = 0;
  virtual void                    yyrestart(std::istream *s)                              = 0;

  virtual int yylex() = 0;

  // Call yylex with new input/output sources.
  int yylex(std::istream *new_in, std::ostream *new_out = nullptr)
  {
    switch_streams(new_in, new_out);
    return yylex();
  }

  // Switch to new input/output streams.  A nil stream pointer
  // indicates "keep the current one".
  virtual void switch_streams(std::istream *new_in = nullptr, std::ostream *new_out = nullptr) = 0;

  int lineno() const { return yylineno; }

  int  debug() const { return yy_flex_debug; }
  void set_debug(int flag) { yy_flex_debug = flag; }

protected:
  char *yytext;
  int   yyleng;
  int   yylineno;      // only maintained if you use %option yylineno
  int   yy_flex_debug; // only has effect with -d or "%option debug"
};
}
#endif // FLEXLEXER_H

#if defined(yyFlexLexer) || !defined(yyFlexLexerOnce)
// Either this is the first time through (yyFlexLexerOnce not defined),
// or this is a repeated include to define a different flavor of
// yyFlexLexer, as discussed in the flex manual.
#define yyFlexLexerOnce

extern "C++" {

class yyFlexLexer : public FlexLexer
{
public:
  // arg_yyin and arg_yyout default to the cin and cout, but we
  // only make that assignment when initializing in yylex().
  explicit yyFlexLexer(std::istream *arg_yyin = nullptr, std::ostream *arg_yyout = nullptr);

  ~yyFlexLexer() override;

  void                    yy_switch_to_buffer(struct yy_buffer_state *new_buffer) override;
  struct yy_buffer_state *yy_create_buffer(std::istream *file, int size) override;
  void                    yy_delete_buffer(struct yy_buffer_state *b) override;
  void                    yyrestart(std::istream *input_file) override;

  void yypush_buffer_state(struct yy_buffer_state *new_buffer);
  void yypop_buffer_state();

  int         yylex() override;
  void        switch_streams(std::istream *new_in, std::ostream *new_out = nullptr) override;
  virtual int yywrap();

protected:
  virtual int  LexerInput(char *buf, int max_size);
  virtual void LexerOutput(const char *buf, int size);
  virtual void LexerError(const char *msg);

  void yyunput(int c, char *yy_bp);
  int  yyinput();

  void yy_load_buffer_state();
  void yy_init_buffer(struct yy_buffer_state *b, std::istream *file);
  void yy_flush_buffer(struct yy_buffer_state *b);

  int  yy_start_stack_ptr;
  int  yy_start_stack_depth;
  int *yy_start_stack;

  void yy_push_state(int new_state);
  void yy_pop_state();
  int  yy_top_state();

  yy_state_type yy_get_previous_state();
  yy_state_type yy_try_NUL_trans(yy_state_type yy_current_state);
  int           yy_get_next_buffer();

  std::istream *yyin;  // input source for default LexerInput
  std::ostream *yyout; // output sink for default LexerOutput

  // yy_hold_char holds the character lost when yytext is formed.
  char yy_hold_char;

  // Number of characters read into yy_ch_buf.
  int yy_n_chars;

  // Points to current character in buffer.
  char *yy_c_buf_p;

  int yy_init;  // whether we need to initialize
  int yy_start; // start state number

  // Flag which is used to allow yywrap()'s to do buffer switches
  // instead of setting up a fresh yyin.  A bit of a hack ...
  int yy_did_buffer_switch_on_eof;

  size_t                   yy_buffer_stack_top; /**< index of top of stack. */
  size_t                   yy_buffer_stack_max; /**< capacity of stack. */
  struct yy_buffer_state **yy_buffer_stack;     /**< Stack as an array. */
  void                     yyensure_buffer_stack(void);

  // The following are not always needed, but may be depending
  // on use of certain flex features (like REJECT or yymore()).

  yy_state_type yy_last_accepting_state;
  char *        yy_last_accepting_cpos;

  yy_state_type *yy_state_buf;
  yy_state_type *yy_state_ptr;

  char *yy_full_match;
  int * yy_full_state;
  int   yy_full_lp;

  int yy_lp;
  int yy_looking_for_trail_begin;

  int yy_more_flag;
  int yy_more_len;
  int yy_more_offset;
  int yy_prev_more_offset;
};
}

#endif // yyFlexLexer || ! yyFlexLexerOnce